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1.
Pharmazie ; 70(8): 553-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26380526

RESUMO

Nine phenolics were isolated from the aqueous ethanol extract of the leaves of Caesalpinia ferrea. The isolates were characterized for the first time from that plant. The structures of all isolates (1-9) were elucidated by conventional methods, spectroscopic analysis, including 1 D and 2D NMR, and by HR-ESIMS as well. The antioxidant capacities using the ORAC method and the cytotoxic activity using the neutral red assay (NRU) for that extract and three major isolates have been evaluated. In addition, the hypolipidemic activity (in vitro and in vivo) of the extract has been assessed.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Caesalpinia/química , Hipolipemiantes/farmacologia , Fenóis/farmacologia , Animais , Linhagem Celular Tumoral , Colesterol/sangue , Sequestradores de Radicais Livres/farmacologia , Hiperlipidemias/sangue , Hiperlipidemias/tratamento farmacológico , Masculino , Fenóis/química , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
2.
Appl Radiat Isot ; 67(7-8): 1259-68, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19282198

RESUMO

The environmental pollution caused by the wastewater from a phosphate fertilizer plant in Egypt was investigated. The concentrations of radionuclides and fluoride in phosphate fertilizer (raw materials, end products and by-products) and other types of fertilizer samples were measured. The concentrations of these elements were also measured in environmental samples (water, sediment and plant) collected from the proximity of outlet of wastewater discharge pipes of the phosphate fertilizer company. The fluoride concentration was ranged from 0.03 to 0.25mg/g, 0.002 to 0.006mg/g, 0.42 to 1.88mg/g and 0.44 to 7.3mg/l for phosphate fertilizer, other types of fertilizer, sediment and water samples, respectively. The activity concentrations of (226)Ra were ranged from 244 to 1312Bq/kg, 0.6 to 12.1Bq/kg, 15.4 to 33.8Bq/kg, 0.06 to 1.3Bq/l and 8.9 to 17.3Bq/kg for phosphate fertilizer, other types of fertilizer, sediment, water and plant samples, respectively. The (232)Th activity concentrations were ranged from 0.7 to 24Bq/kg, 0.7 to 14.5Bq/kg, 10.4 to 19.3Bq/kg, 0.02 to 0.16Bq/l and 2.0 to 29.8Bq/kg for these samples, respectively. Also, the (40)K activity concentrations were ranged from 2.1 to 1.4Bq/kg, 2.1 to 5313Bq/kg, 128 to 281Bq/kg, 0.14 to 0.6Bq/l and 686 to 977Bq/kg for these samples, respectively. Low content of (137)Cs was determined in only two phosphate fertilizer samples (F2 and F3; mean 1.3Bq/kg) and in most of sediment samples (with range 1.0-2.4Bq/kg). The radium equivalent, as a radiation hazard index, was ranged from 284 to 1316, 9.6 to 432 and 47 to 70Bq/kg for phosphate fertilizer, other types of fertilizer and sediment samples, respectively. The results indicated that the wastewater polluted with fluoride produced from the phosphate fertilizer company may be affecting the environment. The radioactivity content measurements indicated that the environment may be slightly affected with low concentrations of (226)Ra and (232)Th isotopes due to the discharged wastewater from the phosphate fertilizer industry. On the other hand, the results of comparison studies for radioactivity concentrations are also presented and discussed.


Assuntos
Fertilizantes , Fluoretos/análise , Resíduos Industriais/análise , Poluentes Radioativos/análise , Indústria Química , Egito , Fosfatos , Plantas/química , Poluentes Radioativos do Solo/análise , Poluentes Radioativos da Água/análise
3.
J Environ Radioact ; 94(3): 129-36, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17368884

RESUMO

The capabilities of some building materials used in Jordan to attenuate gamma radiation were tested. Measurements of the attenuation coefficients of limestone, bricks and concrete have been carried out using a HPGe-spectrometer. Narrow beam technique was used, with a multiple gamma radiation source of different energy lines. Results indicate that variations in the attenuation coefficient for all limestone samples, at the same energy line, are within the experimental uncertainties. On the basis of the results achieved, an empirical formula mu(m)=AE(-0.44) was proposed to calculate attenuation at various incident energies. Limestone of average thickness 7cm was found to stop 75% of a gamma beam of energy 662keV. Meanwhile a brick of effective thickness 7cm was found to stop 60% of the same beam. The total attenuation coefficient of concrete calculated at 1333keV was 11.2m(-1), which is less than that of limestone and bricks.


Assuntos
Materiais de Construção , Raios gama , Carbonato de Cálcio , Exposição Ambiental/prevenção & controle , Jordânia , Radioisótopos de Potássio/análise , Poluentes Radioativos/análise , Espectrometria gama , Tório/análise , Urânio/análise
4.
Environ Health Perspect ; 109(3): 275-82, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11333189

RESUMO

A previous study of six polychlorinated biphenyl (PCB) congeners showed that PCBs with four or fewer chlorines and ortho substitution stimulate uterine contraction frequency in vitro, whereas congeners with a greater number of chlorines or non-ortho substitution are inactive in vitro. We tested the hypothesis that PCB mixtures stimulate uterine contractions in a manner inversely related to the degree of chlorination and the presence of chlorines in the ortho- position of the biphenyl constituents of the mixtures. Uterine strips from pregnant rats were suspended in standard muscle baths and analyzed for changes in isometric contractions in response to in vitro exposure to commercial PCB mixtures (Aroclors) and their dechlorinated products after microbial degradation. The PCB mixtures Aroclor 1242, 1248, and 1254 significantly stimulated uterine contraction frequency, and the least chlorinated mixture, Aroclor 1242, was the most potent stimulant. Microbes from Hudson River sediment dechlorinated Aroclor 1242 and Aroclor 1254 under reducing conditions to produce mixtures with an increased proportion of ortho-substituted congeners with one or two chlorine substitutions. The PCB mixtures that had undergone microbial reductive dechlorination stimulated uterine contraction frequency to a significantly greater extent than the parent mixtures. These results show that increased uterotonic activity was associated with decreased chlorination and increased ortho substitution of the biphenyl constituents of the mixtures.


Assuntos
Poluentes Ambientais/farmacologia , Contração Muscular/efeitos dos fármacos , Bifenilos Policlorados/farmacologia , Útero/efeitos dos fármacos , Animais , Arocloros/química , Arocloros/farmacologia , Feminino , Bifenilos Policlorados/química , Gravidez , Ratos , Relação Estrutura-Atividade
5.
J Exp Zool ; 287(1): 62-73, 2000 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10861551

RESUMO

Specific antibody for chum salmon somatolactin (SL) was used for immunocytochemical investigation of SL cell activity of Mugil cephalus during the gonadal cycle in both natural habitat and captivity. The SL-immunoreactive cells showed strong and specific immunoreactivity to antichum salmon SL. The number of SL-immunoreactive cells increased, as did the secretory and synthetic activity during sexual maturation and spawning in the natural habitat. The SL cells were rather small and moderately immunoreactive in immature fish; they were enlarged, their numbers increased, and they frequently showed more SL immunoreactivity during gonadal development. In addition, during late stages of maturation, small cell size with more or less SL immunoreactive cells were noted, indicating an active release of SL granules. Prespawning females tended to have more enlarged SL cells with stronger immunoreactivity than equivalent males. The SL cells showed an increase in the secretory activity during spawning as indicated by small size and weak immunoreactivity. The SL cells of M. cephalus reared in captivity showed high activity. This may be due to the low concentration of calcium in fresh water. The gradual stimulation of SL synthesis and release during sexual maturation and spawning of M. cephalus suggest that SL may be involved in the control of some steps of reproductive processes, such as steroidogenesis, calcium metabolism, and energy mobilization.


Assuntos
Glicoproteínas/fisiologia , Oviposição/fisiologia , Perciformes/fisiologia , Hormônios Hipofisários/fisiologia , Maturidade Sexual/fisiologia , Animais , Contagem de Células , Feminino , Proteínas de Peixes , Água Doce , Gônadas/citologia , Técnicas Imunoenzimáticas , Masculino , Hipófise/citologia , Água do Mar
6.
Gen Comp Endocrinol ; 113(2): 197-211, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10082622

RESUMO

Using specific antibody for chum salmon somatolactin (SL), immunocytochemical studies were employed to determine the distribution of this hormone in the pituitary gland and the brain of Orechromis niloticus. The results indicated that the SL-immunoreactive (ir) cells are found in the pars intermedia (PI) of the pituitary gland. The SL-ir cells showed strong and specific immunoreactivity to anti-chum salmon SL. Moreover, SL-ir cells were found to be widely distributed in most brain regions. Most of the SL-ir cell bodies were scattered along a nearly continuous line extending posteriorly from the olfactory bulb to the medulla oblongata through the nucleus preopticus periventricularis, habenula, and midbrain tegmentum and ventral to the nucleus lateralis tuberis pars posterior through the nucleus preopticus basalis lateralis and organum vasculosum luminae terminalis. Also SL-ir cells were observed in the cerebellum. The synthetic and secretory activity of the SL-ir cells, in the pituitary and the brain, showed an increase during sexual maturation and spawning. The highly organized SL-containing system and the gradual stimulation of SL synthesis and release during sexual maturation and spawning of O. nilotcus suggest that SL may be involved in the control of some steps of reproductive processes.


Assuntos
Encéfalo/citologia , Glicoproteínas/fisiologia , Hipófise/citologia , Hormônios Hipofisários/fisiologia , Diferenciação Sexual , Tilápia/metabolismo , Animais , Encéfalo/metabolismo , Feminino , Proteínas de Peixes , Glicoproteínas/análise , Glicoproteínas/imunologia , Soros Imunes/química , Imuno-Histoquímica , Masculino , Oncorhynchus keta , Hipófise/metabolismo , Hormônios Hipofisários/análise , Hormônios Hipofisários/imunologia
7.
Environ Health Perspect ; 106 Suppl 6: 1409-18, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9860899

RESUMO

The reductive dechlorination of polychlorinated biphenyls (PCBs) by anaerobic bacteria has recently been established as an important environmental fate of these compounds. This process removes chlorines directly from the biphenyl ring with replacement by hydrogen, resulting in a product mixture in which the average number of chlorines per biphenyl is reduced. In this study, dechlorination of commercial PCB mixtures (Aroclors 1242 and 1254) by microorganisms eluted from PCB-contaminated sediments of the River Raisin (Michigan) and Silver Lake (Massachusetts) caused a depletion in the proportion of highly chlorinated PCB congeners and an accumulation of lesser-chlorinated congeners. Dechlorination occurred primarily at the meta and, to a much lesser extent, para positions of biphenyl. The concentrations of the coplanar congeners including 3,3',4,4',5-pentachlorobiphenyl, the most potent dioxinlike congener, were significantly lowered by reductive dechlorination. Microbial reductive dechlorination of commercial PCB mixtures caused a substantial reduction in biologic activities in several instances. It significantly lowered or eliminated the inhibitory effects of Aroclors on fertilization of mouse gametes in vitro. Similarly, the dechlorinated product mixtures had substantially lower ethoxyresorufin-O-deethylase induction potencies and showed less ability to induce activating protein 1 transcription factor activity as compared to the unaltered Aroclors. In other assays the same dechlorinated product mixtures demonstrated biologic activities similar to the nondechlorinated Aroclors, including the ability of PCB mixtures to stimulate insulin secretion and cause neutrophil activation. The data presented here establish that the biologic activities of commercial PCB mixtures are altered by microbial reductive dechlorination and that an assessment of their toxic potential requires an array of tests that include the different mechanisms associated with PCBs.


Assuntos
Bifenilos Policlorados/toxicidade , Animais , Biodegradação Ambiental , Cloro/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Feminino , Fertilização in vitro , Técnicas In Vitro , Insulina/metabolismo , Masculino , Camundongos , Ativação de Neutrófilo/fisiologia , Oxirredução , Bifenilos Policlorados/química , Bifenilos Policlorados/metabolismo
8.
Neurotoxicology ; 18(3): 857-67, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9339832

RESUMO

PC12 cells were used to examine the mechanisms by which polychlorinated biphenyls (PCBs) reduce cellular levels of dopamine (DA). In cells treated 3 days with Aroclor 1254, 2,2',5,5'-tetrachlorobiphenyl (2,2',5,5'-TCB), or 2,2',3,3',4,4'-hexachlorobiphenyl (2,2',3,3',4,4'-HCB), the PCB-mediated reduction in 3H-tyrosine uptake was observed only at high PCB concentrations that produced a reduction in DNA levels. The PCB congener, 2,2',4,4',5,5'-hexachlorobiphenyl (2,2',4,4',5,5'-HCB) did not produce a reduction in 3H-tyrosine uptake at any concentration tested. Thus, there were PCB concentrations at which a reduction in DA levels did not coincide with a decrease in 3H-tyrosine uptake, suggesting that inhibition of tyrosine uptake was not the primary mechanism by which PCBs reduce DA levels. Aroclor 1254-treated cells also exhibited elevated levels of DOPA, further supporting the conclusion that tyrosine levels were not limiting. Incubation of Aroclor 1254-pretreated cells with 3H-tyrosine resulted in a dose-dependent increase in cellular levels of 3H-DOPA and decrease in cellular levels of 3H-DA, suggesting a PCB-mediated inhibition of the conversion of 3H-DOPA to 3H-DA. When the media was supplemented with DOPA, Aroclor 1254-treated cells still exhibited reduced levels of DA, compared to control cells, even though the control and PCB-treated cells had similar cellular levels of DOPA. Thus, one mechanism by which PCBs may reduce cellular levels of DA is by inhibiting L-aromatic amino acid decarboxylase-mediated conversion of DOPA to DA. The PCB congeners, 2,2',4,4'-TCB, 2,2',5,5'-TCB, and 2,2',4,4',5,5'-HCB, also produced dose-dependent increases in DOPA levels. The congener 2,2',3,3',4,4'-HCB did not produce an increase in DOPA levels, although it did mediate reductions in cellular DA levels. However, when PC12 cells were supplemented with DOPA, all four PCB congeners produced a similar reduction in DA levels, suggesting that the conversion of DOPA to DA was inhibited by the PCBs.


Assuntos
Aminoácidos/efeitos dos fármacos , Carboxiliases/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Bifenilos Policlorados/toxicidade , Animais , Células Cultivadas/efeitos dos fármacos , Dopamina/metabolismo , Relação Dose-Resposta a Droga , Células PC12/efeitos dos fármacos , Ratos
9.
Eur J Immunogenet ; 22(2): 209-13, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7605779

RESUMO

HLA polymorphisms of class I and class II MHC were investigated in 40 Kuwaiti vitiligo patients and in 40 controls using microcytotoxicity assay. HLA-B21, Cw6 and DR53 were increased significantly in patients compared to controls (P = 0.00001, 0.00001 and P = 0.0053 respectively) while HLA-A19, DR52, were significantly decreased (P = 0.00236, 0.05, respectively). Total T-cells, T4 and T8 were measured as CD2, CD4 and CD8 respectively by flow cytometry. Vitiligo patients showed significant increase in CD4 compared to controls (P = 0.03). Our findings suggest that HLA-B21 and Cw6 and DR53, are susceptible genes of vitiligo, while A19 and DR52 are protective genes in the Kuwaiti population.


Assuntos
Genes MHC da Classe II , Genes MHC Classe I , Antígenos HLA/genética , Subpopulações de Linfócitos T , Vitiligo/imunologia , Suscetibilidade a Doenças/etnologia , Suscetibilidade a Doenças/imunologia , Frequência do Gene , Predisposição Genética para Doença , Antígenos HLA/imunologia , Antígenos HLA-B/genética , Antígenos HLA-C/genética , Humanos , Imunofenotipagem , Kuweit/epidemiologia , Fatores de Risco , Vitiligo/etnologia , Vitiligo/genética
12.
Popul Sci ; 6: 41-50, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-12349093

RESUMO

PIP: This study dealt with the possible local tissue reaction induced by IUDs and its possible antifertility role. Premenstrual endometrial biopsies were taken from 50 women using the copper IUD for periods ranging from 5 months to 3 years, together with a control group of 10 nonusers. The immunohistochemical localization of the total immunoglobulins and the immunoglobulin G (IgG) concentrations in the endometrial tissue revealed a significant increase in copper IUD users when compared with the controls. Histochemically, there was a decrease in alkaline phosphatase activity, RNA, DNA, and the acid mucopolysaccharide reactions in the endometrial biopsies from women with copper IUDs. These changes were more apparent in specimens taken less than 1 year after copper IUD insertion, especially in the surface epithelium. The reaction showed progressive increase in the 2nd and 3rd year after copper IUD insertion. It can be claimed that, early after insertion, copper ions, when released in reasonable amounts, lead to metabolic changes in the endometrium, rendering it unfavorable for implantation. It is very likely that, through time, the oxidative changes occurring on the copper wire surface interfered with the release of ions, thus predisposing it to gradually act as an inert foreign body.^ieng


Assuntos
Endométrio , Histocitoquímica , Imunoglobulinas , Dispositivos Intrauterinos de Cobre , Mulheres , África , África do Norte , Biologia , Sangue , Células , Anticoncepção , Países em Desenvolvimento , Egito , Serviços de Planejamento Familiar , Genitália , Genitália Feminina , Dispositivos Intrauterinos , Oriente Médio , Fisiologia , Sistema Urogenital , Útero
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